From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f70.google.com (mail-pg0-f70.google.com [74.125.83.70]) by kanga.kvack.org (Postfix) with ESMTP id 0E6A76B0279 for ; Wed, 14 Jun 2017 18:18:28 -0400 (EDT) Received: by mail-pg0-f70.google.com with SMTP id o62so12280178pga.0 for ; Wed, 14 Jun 2017 15:18:28 -0700 (PDT) Received: from mga03.intel.com (mga03.intel.com. [134.134.136.65]) by mx.google.com with ESMTPS id d11si846945pgt.19.2017.06.14.15.18.27 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 14 Jun 2017 15:18:27 -0700 (PDT) Subject: Re: [PATCH v2 00/10] PCID and improved laziness References: From: Dave Hansen Message-ID: <6da4aea9-ef52-694d-9a03-285c32018326@intel.com> Date: Wed, 14 Jun 2017 15:18:26 -0700 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Andy Lutomirski , x86@kernel.org Cc: linux-kernel@vger.kernel.org, Borislav Petkov , Linus Torvalds , Andrew Morton , Mel Gorman , "linux-mm@kvack.org" , Nadav Amit , Rik van Riel , Arjan van de Ven , Peter Zijlstra On 06/13/2017 09:56 PM, Andy Lutomirski wrote: > 2. Mms that have been used recently on a given CPU might get to keep > their TLB entries alive across process switches with this patch > set. TLB fills are pretty fast on modern CPUs, but they're even > faster when they don't happen. Let's not forget that TLBs are also getting bigger. The bigger TLBs help ensure that they *can* survive across another process's timeslice. Also, the cost to refill the paging structure caches is going up. Just think of how many cachelines you have to pull in to populate a ~1500-entry TLB, even if the CPU hid the latency of those loads. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org